Laparoscopy is a fast growing surgical modality widely used in the treatment of certain prevalent physical ailments. Laparoscopy entails the introduction of an endoscope, light source, and surgical instruments through ports formed in the patient's abdomen. In order to facilitate the procedure, the patient's abdominal cavity is inflated with a suitable gas typically CO2 to give the surgeon additional working area and minimize obstruction. Generally, laparoscopy avoids the risks of laparotomy, which requires the surgeon to open the abdomen and carry out the required procedure by his or her direct viewing.
However, when the laparoscopic procedure requires tissue removal by ablation, several channels through the abdominal wall are required. These include a channel for the laparoscopic camera needed for viewing the surgical field, a channel for the laser or electrosurgical instrument used to burn the target tissue, a channel for insufflation (introduction of CO2 gas into the patient's cavity to expand the patient's cavity) with CO2 gas, and a means for withdrawal of gas and smoke. Note that insufflation with a suitable gas is required during the laparoscopic procedure so as to provide both increased cavity volume and optimal visual conditions during the surgical procedure. A smoke clearing system is usually employed in order to maintain both the visual clarity and proper abdominal pressure within the expanded cavity during the procedure.
A common procedure for positioning the laparoscopic assembly in the patient's abdominal cavity includes first making an incision into the patient's abdominal wall through which a large gauge needle is inserted. A suitable gas, typically CO2, is then introduced into the patient's abdominal cavity through the needle. The needle is then replaced with a trocar, which is then removed leaving behind a sleeve, or cannula, through which a laparoscope is introduced into the abdominal cavity. In order to perform laser or electrosurgery one or two additional small incisions are made in the abdominal wall over the surgical site and cannula/trocar assemblies positioned accordingly. These cannula/trocar assemblies may be used for the positioning of the insufflation tube as well as any other surgical instruments that may be required for the particular laparoscopic procedure.
A laparoscopic procedure typically requires a surgeon to employ either electrosurgery or laser surgery within the confined space of the patient's abdominal cavity. This surgery typically involves tissue burning or ablation. This tissue burning leads to the creation of smoke. Surgical smoke within the confines of a patient's abdominal cavity reduces the surgeon's view of the surgical site, increases the patient's hematocrit levels, and causes delays in the surgery while the smoke is cleared from the laparoscopic field. Efficient removal of the smoke is thus a necessity for the surgical team during the laparoscopic procedure.
Although a laparoscopic evacuation system (“lapevac system”) is effective in maintaining cavity inflation pressure, one problem that occurs during its operation is the clogging of the inlet tube and filter by solid waste, water and humidity carried out of the abdominal cavity by the incoming waste stream. Because the cavity is moist and may be heated above normal temperature by some surgical procedures such as cauterization, surgical wastes can be driven off the cavity wall and internal organs in the form of particles, vapor, and liquids from broken cells and tissues. In addition, vapors within the cavity itself can be drawn into the waste stream. Another problem that may occur during laparoscopic surgery is the insufficient removal of waste vapor from the cavity, stratification of water vapor in the cavity as well as other visualization problems.
Therefore, there is a need in the field for an improved laparoscopic surgical system that is designed to prevent clogging of the inlet and filter by surgical waste and that will reduce or eliminate stratification of smoke and water vapor in the abdominal cavity during laparoscopic surgery